In addition to the simple medical instruments with one functionality, e.g. the opening and closing of scissors as a tool, more recent developments have resulted in medical instruments that have several different functionalities. The German patent DE 197 80 579 B4, for example, discloses a pivotable endoscopic instrument which has a tool in the form of a forceps-like gripping element and which has a second functionality that allows the distal end with the tool to be swiveled relative to the rest of the endoscopic instrument. For actuation of the two functionalities, dedicated actuation devices are provided which are separate from each other and which are arranged at the proximal end of the endoscopic instrument. This arrangement of the actuation elements provided sufficiently good handling and operating efficiency. The increased number of functionalities meant that the range of use of the endoscope was extended and, in this way, the surgical effort during the endoscopic operation was lessened, in particular by a reduction of the insertion and removal from the body.
This development was pursued and led to a medical instrument that has more than two functionalities. This is a tool that is opened and closed and that permits a rotation of the tool and also a pivoting of the distal end with the tool relative to the rest of the medical instrument. Each of these functionalities is operated by a dedicated actuation device at the proximal end. Such an instrument is known from the German laid-open specification DE 10 2012 007 649 A1. This instrument proves very versatile in terms of its possible uses during an endoscopic operation, but it requires thorough training of the operator in order to ensure reliable and safe handling especially under difficult operating conditions.
Furthermore, the European patent EP 2 316 358 B1 discloses a medical instrument with two functionalities that can be controlled in alternation via a single common actuation element. The actuation element is movable to two switch positions, wherein the actuation element is movably coupled to the shank in a first switch position and is movably coupled to the tool in a second switch position, and, therefore, it can either rotate the shank or can open or close the tool. The actuation element has a selector shaft with two coupling parts and, depending on the switch position, the respective coupling part couples with a form fit to one of two mating coupling parts and thus creates the possibility, by actuating the actuation element via the selector shaft with the coupling part coupled with a form fit to the mating coupling part, of transmitting a movement to the tool for opening or closing thereof or to the shank for rotation thereof. This medical instrument has improved ergonomics but is open to improvement in terms of the safety of its handling. This medical instrument of the type in question was used to draw up the preamble.